A264870 - cp's OEIS frontend

A264870 Triangular array: For n >= 2 and 0 < k <= n - 2, T(n, k) equals the number of (unrooted) duplication trees on n gene segments that are canonical and whose leftmost visible duplication event is (k, r), for 1 <= r <= (n - k)/2.

n	a(n)
0	1
1	0
2	1
3	1
4	1
5	1
6	2
7	3
8	3
9	3
10	5
11	8
12	11
13	11
14	11
15	13
16	24
17	35
18	46
19	46
20	46
21	37
22	72
23	118
24	164
25	210
26	210
27	210
28	109
29	227
30	391
31	601
32	811
33	1021
34	1021
35	1021
36	336
37	727
38	1328
39	2139
40	3160
41	4181
42	5202
43	5202
44	5202
45	1063
46	2391
47	4530
48	7690
49	11871
50	17073
51	22275
52	27477
53	27477
54	27477

[1, 0, 1, 1, 1, 1, 2, 3, 3, 3, 5, 8, 11, 11, 11, 13, 24, 35, 46, 46, 46, 37, 72, 118, 164, 210, 210, 210, 109, 227, 391, 601, 811, 1021, 1021, 1021, 336, 727, 1328, 2139, 3160, 4181, 5202, 5202, 5202, 1063, 2391, 4530, 7690, 11871, 17073, 22275, 27477, 27477, 27477]

cp's OEIS Frontend

A264870 Triangular array: For n >= 2 and 0 < k <= n - 2, T(n, k) equals the number of (unrooted) duplication trees on n gene segments that are canonical and whose leftmost visible duplication event is (k, r), for 1 <= r <= (n - k)/2.

Table of values

List of values